Others, though, are terribly uninformed about the risks, as Austin, a former renal dietician, has witnessed. "I can count the times that I had patients say over and over, 'I had no idea that the diabetes could cause my kidneys to fail like this,'" she recalled.

Exacerbated by the nation's obesity epidemic, diabetes is now the sixth-leading cause of death in United States and is rapidly becoming a public health nightmare. The number of U.S. adults who've been diagnosed with diabetes, including pregnant women with gestational diabetes, has increased 61 percent since 1991 and is projected to more than double by 2050, according to the U.S. Centers for Disease Control and Prevention (news - web sites).

Of the 18.2 million Americans who currently suffer from diabetes, 5.2 million don't even know they have it, the U.S. Department of Health and Human Services (news - web sites) reports. Almost all of the undiagnosed cases are people who suffer from type 2 diabetes, a condition in which the body fails to use insulin properly. And, increasingly, it's afflicting people at younger and younger ages -- even children and teens.

Type 2 diabetes usually can be controlled through diet and exercise, but sometimes people require medication or insulin. With type 1 diabetes, which is far less common, the pancreas no longer makes insulin, so patients must inject insulin or use an insulin pump.

When people don't manage their diabetes, glucose and fats remain in the blood, eventually damaging vital organs, according to the CDC's National Center for Chronic Disease Prevention and Health Promotion. The condition can lead to terrible complications:

• Heart disease and stroke cause about 65 percent of deaths among people with diabetes.
• About 42,813 people with diabetes develop kidney failure each year, and more than 100,000 are treated for this condition.
• Some 82,000 people have diabetes-related leg, foot or toe amputations each year.
• Between 12,000 and 24,000 people become blind because of diabetic eye disease.
• About 18,000 women with pre-existing diabetes and another 135,000 women with gestational diabetes who give birth each year face serious complications such as stillbirth, congenital malformations and the need for a Caesarean section.
• About 10,000 to 30,000 people with diabetes die of complications from flu or pneumonia each year.

"This is the kind of disease where vigilance is demanded," said Andrew J. Karter, a research scientist with Kaiser Permanente in Oakland, Calif., who has studied the relationship between genetics and risk for diabetic complications.

Karter's study, published in 2002 in the Journal of the American Medical Association (news - web sites), found no one racial group is more affected by diabetic complications than another. Whites had the greatest risk of heart attack as a diabetes-related complication, while other groups were more likely to suffer from end-stage renal disease.